Pheasant flight pen

Ok im in the process of deciding to take down 4 HUGE pine trees where i want my 40 ft x 25 ft Pheasant pen to be or should i build the pen around them and leave them. I was thinking if i horseshoe nail the flight netting to the pine trees it will help in the sagging dept... Anyone have pros or cons on this idea? A con im thinking is if some day the tree falls. Or the wind but the netting would have some play in it. The trees would be on the inside but the netting would connect to them...

I would if possible,cut the tops off the trees and keep the bottom,I see the problem with attaching the netting to the trees is if you get high winds,like we sometimes get here,60-80 MPH straight line winds the trees will bend enough or come out of the ground enough to pop the netting off and the birds could escape.

keep the trees but don't nail into them. over time, and not much time, the attached wire will girdle and kill the tree. i have the same situation and i'm trying to come up with a solution. some sort of collar the fence attaches to but will not harm the tree. or just framing a self supporting structure around it.